Frequency ratio of an 115In+ ion clock and a 87Sr optical lattice clock
Abstract
We report on the first frequency ratio measurement of an 115In+ single ion clock and a 87Sr optical lattice clock. A hydrogen maser serves as a reference oscillator to measure the ratio by independent optical combs. Over more than 90 000 seconds of measurement time, the frequency ratio fIn+/fSr is determined to be 2.952 748 749 874 863 4(21) with relative uncertainty of 7.0 × 10-16. The measurement creates a new connection in the network of frequency ratios of optical clocks.
0